The present disclosure relates to an information processing apparatus, an information recording medium, an apparatus and method of manufacturing an information recording medium, and a computer program. More specifically, the disclosure relates to an information processing apparatus that can execute a verification processing on various contents requiring content utilization management and prevent illegal utilization of contents, to an information recording medium, to an apparatus and method of manufacturing an information recording medium, and to a computer program.
Various kinds of software data (hereinafter, referred to as ‘contents’), for example, audio data, such as music or the like, image data, such as movies or the like, game programs, and various application programs may be stored in recording mediums, for example, Blu-ray™ disc using a blue laser, DVD (Digital Versatile Disc), MD (Mini Disc), and CD (Compact Disc). In particular, Blu-ray™ disc using a blue laser is a high-density recordable disk, and can store mass movie contents as data having high image quality.
The digital contents are stored in various information recording mediums (recording mediums) and provided to a user. The user plays and utilizes the contents using his own play apparatus, such as a PC (personal computer) or a disk player.
Rights of distribution of various contents, such as music data and movie image data, are generally reserved to writers or sellers. Accordingly, upon distribution of the contents, there is a predetermined utilization limitation, that is, it is configured such that the utilization of the contents is permitted to a legal user, and unauthorized copying or the like is not performed.
According to a digital recording apparatus and a recording medium, recording and playing may be repeated without deteriorating images and sound, but there is a problem in that distribution of illegally copied contents through Internet, circulation of so-called pirated discs, in which the contents are copied to CD-R or the like, or utilization of copied contents stored in a hard disk of a PC or the like spreads.
In the DVDs or mass recording mediums, such as a recording medium using a blue laser, that are being recently developed, mass data for one or more movies may be recorded in one medium as digital information. As such, if movie information or the like may be recorded as digital information, it is important to prevent illegal copying so as to protect a copyright holder. Recently, in order to prevent illegal copying of digital data, various technologies for preventing illegal copying have been put to practical use in the digital recording apparatus and the recording medium.
For example, as for a DVD player, a content scramble system is adopted. In the content scramble system, encrypted video data or audio data is recorded in a DVD-ROM (Read Only Memory), and a key used for decrypting the encrypted data is given to a licensed DVD player. A license is given to a DVD player that is designed to follow a predetermined operation regulation so as not to perform illegal copying. Accordingly, the licensed DVD player uses the given key so as to decrypt the encrypted data recorded in the DVD-ROM and plays images or sound from the DVD-ROM.
Meanwhile, since an unlicensed DVD player does not have the key for decrypting the encrypted data, it cannot decrypt the encrypted data recorded in the DVD-ROM. As such, in the configuration of the content scramble system, a DVD player that does not meet the requirements upon licensing cannot play the DVD-ROM having recorded thereon digital data, thereby preventing illegal utilization.
As one method of preventing illegal utilization of the contents, there is suggested a control configuration that, in an information processing apparatus (play apparatus) that plays the contents, verifies presence/absence of revision of the contents, permits the play of the contents only when it is checked that the revision of the contents is absent, and does not play the contents when it is determined that the revision is present.
For example, in JP-A-2002-358011, there is disclosed a control configuration that calculates a hash value from a reserved contents file to be played, compares a prepared collation hash value, that is, a pre-calculated collation hash value on the basis of legal content data, and the calculated hash value, when the newly calculated hash value is consistent with the collation hash value, determines that the revision of the content is absent, and then progress a content play processing.
In addition, in JP-A-2002-251828, there is disclosed a configuration that calculates a hash on the basis of TOC (Table of Content) data to be recorded as content information, and uses the hash value as verification data.
However, when a processing of calculating the hash value on the basis of the content is executed in such a manner, if the size of content data as original data for the hash value calculation is large, a processing load and a processing time required for the calculation is significantly increased. In recent years, with the progress of high-quality motion picture data, there are many cases where one content has a size of several GB to tens GB. In order that a user's apparatus playing the contents is allowed to perform the hash value calculation processing based on such mass data, excessive data processing ability may be demanded for the user's apparatus. In addition, it may take much time required for verification of the content, and thus the content play processing may not be efficiently performed.
Further, with regards to verification processing based on the hash value, valid verification can be performed only on the content having the registered hash value. Accordingly, for example, when a pirated disc in which an illegal content illegally possessed is additionally recorded on the information recording medium having registered therein the hash value is circulated, even though a hash verification processing routine is executed, the hash verification processing may be executed as verification only for legal content whose hash value is registered, while the detection of the additionally recorded illegal content is not subject to verification. That is, since the detection of the illegal content by the hash verification is not executed, a function of preventing utilization of the illegal content cannot be sufficiently performed.